Production of high quality lubricating oils



Dec. 5, 1933. w. PUNGS Er AL 1,938,083

PRODUCTION OF HIGH QUALITY LUBRICATING OILS Filed Jan. so. 1931 (046%)? l eav'e/r w 4 L INVENTORS Hum-ism PuNqs Hans RHBE Hsamuu zoau BY ATTORNEYS Patented Dec. 5, 1933 UNITED STATES PRODUCTION OF HIGH QUALITY LUBRICATING OILS Wilhelm Pungs, Ludwigshafen on the Rhine, Hans Rabe, Mannheim, and Hermann Zorn, Ludwigshafen on the Rhine, Germany, assignors to I. G. Farbenindustrie Aktiengesellschaft, Frankfort-on-the-Main, Germany Application January 30, 1931, Serial No. 512,488, and in Germany February 3, 1930,

Claims.

The present invention relates to the production of high quality lubricating oils, in particular from paraffin waxes.

It is already known that viscous oils are obtained when olefinic hydrocarbons either alone or in admixture with other hydrocarbons are subjected to the action of catalysts, as for example those of the Friedal craft synthesis such as aluminium chloride and the like. The olefinic hydrocarbons employed for this process may be obtained for example by cracking.

We have now found, contrary to expectation, that when employing products obtained by cracking from paraffinic hydrocarbons, in particular hydrocarbon mixtures comprising parafiin wax, such as petroleum or hard or soft paraifin waxes, the nature of the cracking is of extreme importance for the yields and quality of the lubricating oils to be obtained. For example if the cracking is carried out so that the resulting liquid products are strongly unsaturated'and have an iodine value which is above 150, preferably above 200, the subsequent condensation (under which term we understand also the polymerization) in the presence of catalysts having a condensing action, as for example anhydrous halides giving rise to a strong evolution of heat when treated with water, such as aluminium chloride, iron chloride, zinc chloride, boron fluoride or catalysts having a similar action, yield particularly high quality lubricating oils. The iodine value which, as is known, is the number of parts of halogen, reckoned as iodine, which combine with 100 parts of the oil to be investigated, is determined by treating said oil while dissolved in carbon tetrachloride and in the dark with a fixed amount of a V5 normal aqueous solution of potassium bromate containing grams of potassium bromide per litre and an excess of a 10 per cent hydrochloric acid solution and determining in the known manner the amount of bromine not combined with the oil. The most favourable temperature for a cracking of this kind in which almost all the parafiinic constituents of the initial material to be treated are decomposed with the formation of unsaturated hydrocarbons depends on the nature of the initial material and also on the catalyst added and the apparatus used and must be ascertained in each case by a preliminary experiment. In all cases where cracking temperatures below 600 C. are employed, the process is carried out for example in the presence of dehydrogenating catalysts such as turnings of copper, V2A-steel, masses obtained by sintering a mixture of the powders of copper, iron andnickel, and the initial materials are treated until the content of unsaturated hydrocarbons is as high as possible and the said iodine value has been surpassed.

- This iodine value is surpassed for example by cracking a soft parafiln wax melting at from 40 to 42 C. under ordinary pressure and at a temperature of 540 C. For the same purpose a hardparafiin wax obtained from brown coal tar and melting between 51 and 53 C. is preferably first cracked under a pressure of from 4 to 6 atmospheres and then in a second cracking stage under ordinary pressure and at a temperature of about from 515 to 520 C. An American unwashed wax is cracked under ordinary pressure at about 525 C. Petrolatum is cracked under ordinary pressure at 540 0., the non-converted portion being cracked at 6 atmospheres and the pressure-cracked products being subjected to a temperature of 530 C. With other parafiinic hydrocarbon materials it may easily be determined by preliminary experiment, which order of sequence of the single cracking stages provided several steps are employed, what temperature and velocity of flow are most suitable for obtaining a product having an iodine value of more than 150.

When working under ordinary pressure it is preferable for the sake of economy to reduce the formation of gas to a minium. The formation of gas is dependent on the temperature and on the velocity of the treated materials. With the same velocity of flow the losses by formation of gas are greater at higher temperatures than at lower temperatures, whereas with the same temperatures these losses are greater at lower velocities of flow than at higher velocities of flow, so that at higher temperatures greater velocities of flow may be employed. On account of the high cracking temperatures the cracking operation is carried out in the vapor phase it ordinary pressures are employed.

Particularly good results are obtained by cracking the initial parafiinic hydrocarbons first under an elevated pressure, which may range to about 10 atmospheres, and at a moderately elevated temperature, and then subjecting the products thus obtained to further cracking under ordinary pressure and at higher temperatures. The sequence of these stages may also be changed, if desired. When working in several stages in the manner'described the loss by evolution of gas is less than when cracking only in one stage and under ordinary pressure. On the other hand, if the cracking were carried out only at elevated 11o pressures, the liquid products formed in good yield would have so low an iodine value that unsatisfactory amounts and qualities of lubricating oils would be obtained in the subsequent treatment with aluminium chloride. The cracking under elevated pressure followed or proceeded by the cracking under ordinary pressure combines the advantage of small losses by the formation of gas with that of the obtention of satisfactory yields of sufficiently unsaturated compounds.

When a condensing agent as for example aluminium chloride is added to the cracking products obtained, a considerable increase in temperature takes place, and this is preferably regulated so that a temperature of 150 C. is not exceeded. External heating is often superfluous and may in some cases even reduce the yields. The unsaturated hydrocarbons to be condensed and the condensing agent are advantageously mixed together at ordinary temperature. Up to 90 per cent of lubricating oils are obtained from the cracking product. About two thirds of these are hot steam cylinder oils having a flash-point of above 325 C. and a viscosity of 6 Engler at 100 C.

Cyclic hydrocarbons, as for example naphthalene, anthracene, cyclohexene or terpenes, which take part in the formation of lubricating oils, may also be added to the materials cracked as hereinbefore described before the condensation and polymerization. In this case also, special heating is unnecessary. Lubricating oils are then obtained which, by virtue of their fiat temperatureviscosity curve, are suitable for lubricating automobile motors, either alone or in admixture with other synthetic or natural oils.

Itshould be understood that the said iodine values are those determined according to Winklers method (see Holde Kohlenwasserstolfole und Fette, VI edition, page 583).

The accompanying drawing showing in a somewhat diagrammatic manner an elevation partly in section of a plant particularly suitable for carrying but the process described will further assist in fully understanding the nature of the present invention.

Referring to this drawing in detail numerals 1 and 2 denote cracking vessels in which the initial parafiinic hydrocarbons are cracked.' Vessel 1 into which said hydrocarbons are introduced by way of pump 3 is maintained under an elevated pressure which may range up to 10 atmospheres. The products partly cracked in the said vessel are then passed by wayof pressure release valve 4 in the second cracking vessel 2 in which cracking is completed under ordinary pressure. Vessels 1 and 2 may contain suitable cracking catalysts resting on perforated plates 5 and 6 respectively. The cracked products issuing from vessel 2 are then passed through cooler '7 and from thence into vessel 8 into which cyclic hydrocarbons are also'added at 10. A rotatable stirring device 9 provides for intimately mixing said cyclic hydrocarbons with the cracked products. ,The mixture obtained is then conveyed by way of cock 11 into the condensation vessel 13 in which it is subjected to condensation by means of aluminium chloride supplied at 14. The temperature of said condensation vessel 13 may be regulated by a suitable fluid agent such as wet steam passed through the jacket 12 surrounding said vessel 13. The condensed products are then led into vessel 15 in which they are treated with water introduced at 16. The upper oily layer formed in this vessel is withdrawn at 17 and may be further worked up by fractional distillation while the wa e having dissolved out of the waste aluminium chloride from the condensation products is withdrawn at 18.

The following examples will further illustrate the nature of this invention, but the invention is not restricted to these examples. The parts are by weight.

Example 1 100 kilograms of soft paraflln wax melting between 38 and 40 C. are cracked at 440 C. and under a pressure of 3 atmospheres. 5 kilograms per hour of the resulting product are then led under ordinary pressure and at from about 480 to 500 C. over a catalyst consisting of porous iron and nickel into a column having a; volume of 15.5 litres. 85 kilograms of liquid products having an iodine value of 210 are thus obtained.

100 kilograms of the said liquid products are then mixed in a stirring vessel with 8 kilograms of anhydrous aluminium chloride whereby the temperature rises to 110 C. The temperature is then maintained at this point for about one hour, whereupon the treated materials are cooled, blended with 100 litres of water and stirred for half an hour. The resulting oil has a pale colour. The oily layer and the aqueous layer readily separate from each other. After distilling off the benzine fraction, the oil is distilled up to 300 C. First runnings of low viscosity, amounting to about 8 kilograms are first obtained and then 15 kilograms of lubricating oil of medium viscosity and 6 kilograms of cylinder oil having a flashpoint of 290 C. and a viscosity of 3.5 Engler at 100 C. The residue consists of 42 kilograms of a hot steam cylinder oil having a flash-point of 325 C. and a viscosity of 6.6 Engler at 100 C.

Example 2 100 parts of soft paraifin wax having a melting point of 42 C. are cracked as described in Example 1 under a pressure of 3 atmospheres and at a temperature of 440 C. The resulting liquid products are then passed'in the vapour phase at 500 C. and at the same velocity of flow as described in Example 1 over pieces of calcium silicide, so that a cracking product having an iodine value of 280' is obtained. This is led into a stirring vessel containing 100 parts of decahydronaphthalene,'10 parts of naphthalene and 8 parts of anhydrous aluminium chloride. After stirring for three hours at 20 0., water is added to the contents of the stirring vessel. After separating the aqueous acid aluminium chloride solution, the cyclic hydrocarbons still present are distilled oil and the oils of low boiling point and low viscosity removed by vacuum distillation. 60 parts of a very viscous lubricating oil are obtained having a flat temperature-viscosity curve and a. viscosity of 48 Engler at 98 C. and 85.9 Engler at 38 C.

Example 3 100 kilograms of soft parafiin wax are passed at ordinary pressure, at a. temperature of 500 C. and with a velocity of flow of 9 kilograms per hour through a tower having a. volume of 15 litres and which is filled with pieces of pumice.

The resulting products are further treated at' iodine value of 250 are thus obtained. Theseproducts are then polymerized by the addition of 8 kilograms of aluminium chloride and worked up as described in Example 1. V I

What we claim is:

1. A process for the production oi lubricating oils, which comprises subjecting at between ordinary temperature and 150 C. to the action 0! an anhydrous halide giving rise to a strong evolution of heat when treated with water a mixture 0! a cyclic hydrocarbon with liquid products obtained by cracking a hydrocarbon mixture comprising parafiin wax in the vapor phase and which liquid products have an iodine value of more than 150.

2. A process for the production of lubricating oils, which comprises subjecting at between ordinary temperature and 150 C. to the action 01 an anhydrous halide giving rise to a strong evolution of heat when treated with water a mixture of naphthalene with liquid products obtained by cracking a hydrocarbon mixture comprising parafiin wax in the vapor phase and which liquid products have an iodine value of more than 150.

3. A process for the production of lubricating oils, which comprises subjecting at between ordinary temperature and 150 C. to the action or an anhydrous halide giving rise to a strong evolution of heat when treated with water a mixture of a cyclic hydrocarbon with liquid products obtained by cracking paraflin wax in the vapor phase.

4. A process for the production of lubricating oils, which comprises subjecting at between ordinary temperature and 150 C. to the action 01' an anhydrous halide giving rise to a strong evolution 01' heat when treated with water a mixture 01 a cyclic hydrocarbon with liquid products obtained by cracking paraffin wax in the vapor phase and which have an iodine value of more than 200.

5. A process for the production of lubricating oils which comprises subjecting at between ordinary temperature and 150 C. to the action oi an anhydrous halide giving rise a strong evolution of heat when treated with water a mixture of a cyclic hydrocarbon with liquid products obtained by cracking a hydrocarbon mixture comprising a paraflin wax in more than one stage of which at least one is carried out under elevated pressure in the vapor phase and another under ordinary pressure, and which liquid products have an iodine value of more than 150.

WILHELM PUNGS. HANS RABE. mJRMANN ZORN.

What we claim is:

1. A process for the production of lubricating oils, which comprises subjecting at between ordinary temperature and 150 C. to the action 01' an anhydrous halide giving rise to a strong evolution of heat when treated with water a mixture of a cyclic hydrocarbon with liquid products obtained by cracking a hydrocarbon mixture comprising paraflin wax in the vapor phase and which liquid products have an iodine value of more than 150.

2. A process for the production of lubricating oils, which comprises subjecting at between ordinary temperature and 150 C. to the action of an anhydrous halide giving rise to a strong evolution of heat when treated with water a mixture of naphthalene with liquid products obtained by cracking a hydrocarbon mixture comprising paraffin wax in the vapor phase and which liquid products have an iodine value of more than 150.

3. A process for the production of lubricating oils, which comprises subjecting at between ordinary temperature and 150 C. to the action of an anhydrous halide giving rise to a strong evolution of heat when treated with water a mixture of! a cyclic hydrocarbon with liquid products obtained by cracking paraflln wax in the vapor phase.

4. A process for the production of lubricating oils, which comprises subjecting at between ordi-' nary temperature and 150 C. to the action of an anhydrous halide giving rise to a strong evolution 01' heat when treated with water a mixture of a cyclic hydrocarbon with liquid products obtained by cracking parailin wax in the vapor phase and which have an iodine value of more than 200.

5. A process for the production of lubricating oils which comprises subjecting at between ordinary temperature and 150 C. to the action of an anhydrous halide giving rise a strong evolution of heat when treated with water a mixture of a cyclic hydrocarbon with liquid products obtained by cracking a hydrocarbon mixture comprising a paraffin wax in more than one stage of which at least one is carried out under elevated pressure in the vapor phase and another under ordinary pressure, and which liquid products have an iodine value of more than 150.

WILHELM PUNGS. HANS RABE. HERMANN ZORN.

CERTIFICATE OF CORRECTION.

Patent No. 1,938,088.

December 5. I933.

WILHELM PUNGS, ET AL.

it is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 8, for "craft" read Craft; line 16, for "petroleum read petrolatum; and line 85, for "minium" read minimum; and page 3, line 87, claim 5, after "rise" insert the word to; and that the said Letters Patent should'be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 27th day of August, A. D. 1935.

(Seal) CERTIFICATE OF CORRECTION.

Patent No. 1, 938,088.

December 5, 1933.

WILHELM PUNGS, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 3, line 92-93, claim 5, strike out the words "in the vapor phase" and insert the same after "pressure" and before the coma in line 94, of said claim; and that the said Letters Patent should be read with this correction therein that the some may conform to the record of the case in the Patent Office.

Signed and sealed this 24th day of September, A. DJ 1935.

(Seal) Leslie Frazer Acting Commissioner of Patents. 

